


The Membrane Siblings

by sparkeedle



Category: Invader Zim
Genre: Adult Language, F/F, Sibling Bonding, Slight Violence
Language: English
Status: In-Progress
Published: 2018-11-17
Updated: 2018-11-24
Packaged: 2019-08-24 18:31:44
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,401
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16645571
Author URL: https://archiveofourown.org/users/sparkeedle/pseuds/sparkeedle
Summary: A collections and prompts and drabbles surrounding Dib Membrane and his little sister, Gaz. The professor and Zim will occasionally make appearances.





	1. Daily Routine

Prompt: _Daily Routine_

 

Every day starts the same. Dib and Gaz are awoken by a preset recording of their father cheerfully waking them up. Dib would wake Gaz himself, but she can’t stand the sound of his voice (especially so early the morning). When they were little their father used to wake them up in person, but he doesn’t have time for that anymore.

It’s always a childish race to the bathroom and Dib has longer legs most of the time. Most of the time he uses up all the hot water and Gaz hurls a boot, a cereal bowl, or maybe a picture frame at him to remind him to be more considerate.

On Tuesdays and Thursdays Gaz has soccer practice, which isn’t her idea. Her father signed her up to deal with her “handsy outbursts” with her brother and with those at school.

“Something _physical_ might help relinquish all that DARK energy, daughter!” he had told her with a concealed smile, face hidden by his high collar.

Of course, he says this over a video feed from his laboratory- which is half way across town.

So, on Tuesdays and Thursdays Dib French plaits Gaz’s hair into two little bundles and she tries to make it last the whole school day. If it doesn’t, he repairs the fly-always and loose pieces on the way to the field.

After the initial braiding they eat their appropriate cereals. Sometimes Dib runs out of his brand and borrows some of Gaz’s in which she flings an orange or a milk carton at him-to remind him to _ask first._

In the warm seasons they walk to school and Gaz has perfected tuning out his inane ramblings. In the colder seasons they take the bus and she plays her GameSlave. Every third time she dies Dib _might_ get a turn.

After some hairbrained adventure with the weird, green kid from Dib’s class they get home to yet another automated message and eat dinner. Usually the house’s AI prepares the dinner in some fashion, but when it dysfunctions Dib has to make do. He usually makes them mac n’ cheese or orders a pizza.

Most of the time after Dib is permitted ONE episode of Mysterious Mysteries Gaz falls asleep playing on the living room console. Gaz is nicest to Dib when she’s asleep.

He helps her into her pajamas and puts her to bed like their father used to. Dib knows their father will eventually get around to sleeping at the house more, but for now Gaz is his responsibility. Even though she insists (begrudgingly) it’s the other way around.

Dib crawls into bed and stares at the ceiling, usually for about three hours. Gaz was always the easiest to fall asleep. When he does wake up it’s to a preset message of their father. He races Gaz to the bathroom.

Lather. Rinse. Repeat.

**Notes for the Chapter:**

> Sorry this chapter is so short! I had an idea and ran with it. I wanted to explore the relationships that we don't get to see on the show- the tender parts disguised by the monotony of the Membranes' daily routine.


	2. Crush

**Summary for the Chapter:**

> Prompt where Gaz has an unhealthy crush and Dib helps her deal with it.

Prompt:  _Crush_

 

Gaz is usually quiet, and Dib can tell the difference between her indifference and seething silence. This time is different, however. Her face is red and one of her braids is tangled in a downward mess. She’s not in her practice uniform which is weird because Gaz usually doesn’t change back into her school clothes after practice.

He’s spent the whole afternoon waiting on her (per his father’s tedious instruction) in the computer lab, writing a blog about the  _Mothman_.

“Gaz is quite resourceful, but she’s still your little sister and needs to be protected!” his father had said.

Sometimes Dib watches her at soccer practice and secretly admires how damn near lethal she is with the ball.  Today he has chosen to opt out and almost regrets it when she meets him in their usual spot: the playground.

They do not resume their daily afternoon walk. Gaz fumbles with the hem of her sweatshirt and Dib stands in awe of this spectacle.

“What’s wrong?”

She kicks gravel in his direction. He sighs, taking the hit. He decides to remain rooted until she says something because he knows that  _she knows_  she’s not allowed to leave without him. 

“Well, it looks like we’re gonna camp out here tonight. I can take the slide and you can take the tunnel,” he shoved his hands in his pockets, and continued, “We can stake out that librarian eating goat that lives in the crawl space of the gym-“

“Jenny Finkman has my GameSlave.”

Dib knew if he rambled long enough Gaz would have either told him to shut up or the reason why-and he’s extremely shocked.

“But-why- _Jenny Finkman?_ ” he replies incredulously, having trouble with a more sophisticated inquiry. Jenny was a bouncing blonde and burped extremely loud in the cafeteria. She was adorable and on Gaz’s soccer team. He had a theory she was really a succubus.

Gaz didn’t answer and didn’t meet his eyes, only scowling.

“Why does Jenny Finkman have your GameSlave?” he asked.

“She wanted to borrow it-“

“Ok _ay,_ but I thought-“ He never got to play it so why in the hell would  _Jenny Finkman_  get to?

“Just  _drop it, okay.”_  

She turned sharply and shuffled to the swings-and oddly to Dib, actually began to swing. Gaz never really played at recess. She always sat under a tree with her game and sometimes participated in kickball. She didn’t play on the equipment, especially not with the others. Gaz didn’t ‘bond well’ with the other children, as their father had put it.

So what possessed her to let Jenny Finkman borrow her GameSlave?

Dib walked up to her, swiftly avoiding her boots when she swung towards him.

“Are you friends?” he called up when she swung upwards.

“I don’t know!” she barked.

Gaz didn’t let people borrow her things-sometimes she let Dib play with her, but Dib wasn’t allowed to use her stuff per say. Only the professor was allowed to do that and that’s only because Gaz actually liked him.

“Do you like her?”

Gaz didn’t answer.

Dib sat on the adjacent swing and followed in her suit. He tried to keep pace with her but ended up swinging in her opposite. Each time they met in the middle was when he tried to resume conversation.

“Well, if you do--it’s okay—I don’t think it’s bad—if you like her—!”

Gaz’s heels dug into the gravel, effectively bringing her to a wobbly halt. She didn’t say a word.

Dib jumped out of his swing and panted back over to her, hands gripping his knees.

“She borrows my homework and lunch money sometimes.”

“Gaz--?” he straightened up. Was this girl taking advantage of her?  _His_ sister?  _The_ Gaz Membrane?

"Have you ever told her no?”

“Once.”

“What happened?”

“She pushed me.”

“Did you push her back?”

“No.”

“No?”

“ _No_.”

Dib wondered who had replaced his sister and where his real one was-the one who would’ve knocked this little blonde’s lights out had she even laid a hand on Gaz. Gaz did not suffer fools.

“Why not?”

“Every time I try my face gets hot and she laughs at me.”

Dib couldn’t contain his smile, despite his sister’s apparent bullying. It was almost cute had she not been nearly physically breaking him with her glare.

“Gaz…I think you have a crush.”

She socked in him she shoulder, sending him stumbling to the gravel with a deafening  ** _OW._** He clambered up, vigorously massaging his invisible wound.

“I don’t wanna have one,” she finally said, placing her words carefully. 

He sighed, “I know. She sounds like a jerk.”

“How do I stop?”

He couldn’t believe his ears. She was asking for his advice. He could practically sense her internal cringing. Parts of it were visible on her face, its features contorting in embarrassment and disgust.

He tapped his chin, abandoning his sore shoulder, “Well, you need to stand up to her. Tell her no.”

“I can’t.”

“You could push her back.”

“I can’t.”

“Why not?”

“I just get all red!”

“Hmm, well  _I_ can’t do it. I doubt she’d give your game back to me. Plus, if  _I_  pushed her I’d get into a lot of trouble being a boy n’ all. I don’t know any girls that could help us.”

“ _Some_ one has to push her,” Gaz grumbled.

“Mm…yeah. Someone. Or some _thing_.”

Dib couldn’t believe what he was about to do.

 

\-- The Next Day

 

Jenny Finkman was tackled in the corner of the playground. Gaz’s GameSlave was knocked from her grasp and luckily landed neatly in a soft pile of dirt. Jenny’s bewilderment was given its reason when she was greeted by a green, familiar face.

Everyone knew about the green weirdo who wore the same pink clothes every day. The little boy (as most presumed he was) told every one it was a skin condition, but his lack of ears and nose still freaked her out.

“What was that for?” she cried, sitting up, rubbing her head where it made contact with the ground.

Zim stood tall, gloved hands ornamenting each hip. “Zim has been instructed to tell YOU,  _disgusting,_ pale worm  _babEEE_ that if you use the Gaz-human for any false love pig favors then-“ He peered downward at the palm of his glove, examining the scribble.

“-the  **FINK** will pay! Understand? The FINK  **will PAY**! And Zim will do things more sinister than the push!”

“But-“ she sputtered in defense, “-you’re a boy. You can’t push me!”

He leered at her closely.

“You don’t know  _what_ Zim is. And you  _don’t_  want to find out if you want to keep suffering your pitiful existence, FINK.”

Zim whirled around to the Membrane siblings, perched at a distance at the jungle gym and gave them a thumbs up.

“How did you get him to do that?” Gaz quirked a brow.

“I told him I’d tell him one of the human race’s weakness if he did us a favor.”

“What was the weakness?”

Dib grinned, “Reversing pollution caused by greenhouse gases.”

She shook her head, “You’re so weird.” They began to stroll towards her discarded game.

He shrugged, “I told him humans thrive by eating pollution.”

“Why?”

“So he’ll actually be saving the earth when he thinks he’s destroying it!” Dib burst in a loud laugh.

“Diabolical,” she deadpanned and scooped up her prize, cradling it to her chest.

“I know right?” he beamed, “Let’s go home." 

**Notes for the Chapter:**

> I have a headcanon that Gaz's outlet for her anger is the school's soccer team. 
> 
> Dib is a good brother (when he wants to be). 
> 
> I also have always liked the idea of no one really knowing what Zim is. Zim drop kicks your typical gender roles in the squeedlyspooch.


	3. Hungry

**Summary for the Chapter:**

> AU where Dib believes Gaz has been bitten by a vampire

Prompt:  _ ~~Vampire~~_

 

Dib had finally fit himself into a comfortable position on his bed. His brain never silenced, therefore sleep seemed impossible most nights. Gaz did not have this problem. Their father often said she slept like the dead and even though Dib knew his father spoke figuratively, he often wondered if Gaz was fully human. The nine-year-old was the physical embodiment of rage- a pooling darkness seemed to consume the room whenever she appeared.  _Which_  was sometimes out of nowhere.

Dib wanted to investigate this matter his whole life, but she never would let him get close enough to. She was saturated with some kind of dark, supernatural force.  _That_  he could tell from the distance she allowed.

He had asked his father once about her origin.

“Why, SON, you already know the answer to that! I developed Gaz in my lab like I did you!  _Although_  unlike you I had to  _modify_  her traits in terms of her  _physicality_ -you could say.”

“Did you give her all her creepy powers then?”

“Creepy powers, eh? Your sister may be  _intimidating,_  son, but I assure she is a perfectly normal girl! In fact, that is the extent of her modification!” he explained, fiddling at the counter with a soldering gun in one hand and naked wires in the other.

“Being normal?” Dib stuck out his tongue.

“Being a  _girl_ ,” his father corrected him with the waggling of his index finger.

“But she can levitate!” Dib flung his hands up.

“And  _you_  can raise the dead,” his father retorted, turning back to his work.

“I said I was sorry!” Dib huffed.

 _Great,_  Dib thought to himself. His mind ran off on another tangent and he was wide open.

A little shadow loomed in his door.

Now he was seeing things.

He recognized the shape and his paranoia was only slightly alleviated. Gaz only came into his room at night when she was angry at him. Not knowing what he could’ve done this time to deserve her wrath he readied his arms to shield himself anyway.

She remained still, hovering silently in the hallway light.

He lowered his hands and leaned closer to better inspect her. Her face was sullen, her eyes hardly open. Her left side had long streaming stains of red running down her pajamas.

“G-Gaz?”

He tentatively crawled out of bed and tiptoed towards her. Had she hurt herself?  _Or someone else?_

“I’m hungry,” she said in a low voice, sultry and black.

With a gentle hand he took a hold of her chin and tipped her head back. He searched for the wound’s source but whatever or wherever it was, it was being obscured by the blood.

He guided her easily to the bathroom with soft prodding, whispering the whole time. “What happened? Did you cut yourself. Did you  _cut someone_?”  

Gaz never answered him, only teetering back and forth with each step. He could hear her stomach growling. She really  _was_  hungry.

Their father wasn't home, per usual, and Dib was used to tending to minor scrapes and accidents when it came to his sister. She never thanked him or said a word. She let him to his work and then bounded off somewhere else, usually to her room or the kitchen.

He sat her down on the toilet seat and rummaged under the sink for supplies. He couldn’t locate the first aid kit but did manage to score washcloths and some salve. He didn’t know if he would need bandages at this rate, but there was only one way to find out.

It’s not like she would tell him anyway. When Gaz got in one of her moods, especially when she wasn’t well, it was like trying to coerce an eggplant.  

He turned on the faucet and waited so the water would be a little past tepid, but not too warm. He began to follow the trail of blood upward, dabbing it on her skin with a damp cloth.

“You still don’t wanna tell me?” he tried one last time.

Gaz was still silent.

He sighed and continued his task, washing up the blood until the rag was pink. So, far he hadn’t discovered any scratches or sores. Just bloody skin. He made his way up to her neck and she flinched.

“Sorry,” he mouthed, absentmindedly.

He scrubbed lightly until he unearthed two circular wounds from under her collar, hardly the size of peas.

His face immediately went pale.

“I’m hungry,” she drawled again, her voice in a low moan as if she was ill.

Her small hands encircled his throat, clamping down with a steel like strength he didn’t know she had. His oxygen was cut off immediately and he tried to scramble backwards, but her grip was too strong.

“I’m  _hungry, Dib_.”

\--

When Dib awoke his whole body screamed at him, erupting with aches which mostly were gathered at the back of his head. He must have fainted he figured, and decided to take it slow.

He urged himself to sit up slowly and realized everything was blurry. His glasses were strewn somewhere and after blindly feeling around he found himself to be successful. Sitting up was worse than laying down, but it wouldn’t do him any good to remain on the tile.

 _Gaz._ His entire nervous system exploded in fear and worry. He could hear soft little breaths carrying on from the depths of the tub. He peeked over the edge and found his terrifying sister actually looking adorable. Gaz had seemingly climbed in the tub and fell asleep.

Her mouth was stained cherry.

Dib immediately went into a fit and pried off his clothes, searching every angle and end of his body. Nothing.

He slapped at the itching sensation on the back of his neck.

“Get out. I need to pee.”

Gaz’s voice sent him nearly shooting into the ceiling. She crawled out of the tub, sneering at him. “Ew! Put  _some clothes on_ , freak.”

Dib was shoved back out into the hall before he could protest.

 

\--

 

Gaz hadn’t touched her cereal and he knew it was her favorite. He sat across from her at the kitchen table while the house’s AI prepared his SUPERToast TM.

“Stop staring at me.”

Dib  _was_  practically burning holes through her. “Gaz, what happened last night?”

“I don’t remember.”

“Oh come on.  _Something_  bit you. You were covered in blood and you kept telling me you were hungry! What does that sound like to you?“ In his gut Dib  _knew._ It was too obvious. Then again it wasn’t the first time Gaz has choked him to unconsciousness.  **But** , something had bitten her.

“Sounds like you’re crazy,” she mocked him, stirring her cereal around with her spoon.

“Why aren’t you eating?” he asked.

“Not hungry.”

“You were last night,  _that’s_  for sure.” It was the only thing he could get out of her. A terrible notion inked into his mind. Gaz must have suppressed her hunger somehow.

“Did you eat something?”  _Someone?_

“I’m going to eat you if you don’t shut up.”

Dib was put back into his silence, ignoring his breakfast which had been placed before him. He made a note to watch her closely. Perhaps it was all in his head. He hadn’t been wrong before, though, and he watched Gaz crawl in her bed to go to sleep that night. How would a vampire even have a chance at biting her?

It would have to be invited in.

His eyes went wide.

\--

Dib armed himself with a wooden stake, ordered directly from  _ParaMonthly Magazine,_ and an industrial flashlight. First was the basement which only offered cobwebs and defunct inventions via his father. The attic yielded the same results along with every hall closet and cupboard. His own room was still a safe heaven and was empty. His father’s room was as empty as it usually was. He found nothing but dust.

That only left one room. His sister’s room.

He wasn’t sure if he’d rather die by hands of an intrusive vampire or his sister, and since it might be both, he thought perhaps he had nothing to lose.

He pushed her door open and shined the light upon every crevice and corner without actually entering. He sighed, knowing he’d actually have to enter if he was going to get anywhere. Gaz was in the living room absorbed by  _Bloodswine Slayer III_ , so he knew he had a small window before she beat the next level and noticed that his annoying voice was missing.

He crossed the threshold with trepidation. He flung open her closet doors, finding nothing but sweaters, skirts, and abandoned toys.  He could feel a chill creeping up his spine and ending at the itch on the back of his neck which he slapped in attempt to keep from scratching it.

He crept over to the bed and kneeled, drawing up the bed skirt with a shaking hand.

“What’re you  _doing in here?”_

His head knocked into the underside of the frame and before he could offer an explanation for his actions he was dragged out by his ankles.

Gaz brooded into him in the dim light of her room, nails digging into his shoulders. She had him pinned to the wall, his toes hardly touching the carpet.

“ _What are you looking for, Dib_?” her voice darkened, wavering between octaves. “ _Did you lose something?”_

He trembled under her hold, his voice cracking, “Did you let a vampire in the house? Did it turn you?” 

She laughed in his face, forgoing an answer.  She released him, and he crumpled to the floor, cowering before her. The stake was still in his clutch.

“Is that what you think, Dib? That a vampire bit me?”

“Yes,” he answered sheepishly, grip tightening on his weapon.

“You’re a moron.”

“What?”

“I left my window last night and a snake got in.”

“You’re kidding me.”

“Duh.”

She launched at him, fangs sinking into their previous spot on the back of his neck. The fit perfectly like a key into its lock.

Dib’s world went dark.

**Notes for the Chapter:**

> Thanksgiving was yesterday, but I'm still feeling slightly Halloweenish. I've been playing with this idea for awhile and decided to just go for it. 
> 
> I might write a part two - who knows!


End file.
